Electronics, Lighting, & Gadgets - How many lumens for 25 MPH

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View Full Version : How many lumens for 25 MPH


Lamourish
07-12-07, 09:12 PM
Hello all,

I'm a heavy commuter and my schedule has shifted. I ride almost the entire ride on streets with cars; about 3/4 of the ride has a healthy shoulder. Come fall I'll be riding in the dark. My current max speed is approximately 27 MPH with an average around 19 on a MTB uglified conversion. I have a set of ghetto lights now that let me roll at about 10 MPH for after work emergencies. However, if I'm going to keep commuting I want to be full speed in the dark. I was wondering what kind of Lumen output I would need to consider (ballpark), since it seems to be the most important part of the package. I understand lens, reflector, etc. make a difference but any advice on sheer light would be appreciated.

My budget is ~300 USD$, with a stretch if really warranted. I like the idea of LED with a conversion for night running...but that's a secondary motivator.

Thanks!


gretnabikes
07-13-07, 08:14 AM
Boy I could help you out with the conversion for running and everything, but I don't think you would like the price.

Lamourish
07-13-07, 08:30 AM
Lay it on me :)

If I'm not being realistic, then I should reconsider. I suppose.

Thanks.


gretnabikes
07-13-07, 12:58 PM
Well just an option for you would be the WilmaX kit. It's 830 LED lumens, the kit comes with both mounting for handlebars, and it comes with a headband, so you could go running with it.
Check it out here (http://gretnabikes.com/item.asp?PID=75&cID=1&scID=2)

Grun
07-13-07, 07:33 PM
Hello all,

I'm a heavy commuter and my schedule has shifted. I ride almost the entire ride on streets with cars; about 3/4 of the ride has a healthy shoulder. Come fall I'll be riding in the dark. My current max speed is approximately 27 MPH with an average around 19 on a MTB uglified conversion. I have a set of ghetto lights now that let me roll at about 10 MPH for after work emergencies. However, if I'm going to keep commuting I want to be full speed in the dark. I was wondering what kind of Lumen output I would need to consider (ballpark), since it seems to be the most important part of the package. I understand lens, reflector, etc. make a difference but any advice on sheer light would be appreciated.

My budget is ~300 USD$, with a stretch if really warranted. I like the idea of LED with a conversion for night running...but that's a secondary motivator.

Thanks!
You can try for a DualCross from Cygolite ($160-$180), which probably puts out around 400 lumens, since it is comparable to a 20W Halogen system, with adjustable intensities, and various modes, and battery indicators. Pair it up with two Fenix P3D CE ($120) that shoot out another 320 lumens giving you around 720 lumens and falling in your budget around $300. If you wanted you could add a Cree Edition Ultrafire LED torch from dealextreme for another $20, and probably gain another 100 lumens. You could mount this on your helmet, or to serve as a backup light.

I use the weaker L2D CE ($60) from Fenix and it still pumps out a decent amount of light, even at 135 lumens, it beats the pants off the Light and Motion Vega at 85 lumens and $150-$180.

http://www.performancebike.com/product_images/500/40-2415-NCL-ANGLE.jpg
http://www.fotonmag.cz/wp-content/uploads/2007/02/fenixl1dl2d.jpg
http://www.dealextreme.com/productimages/sku_1993_1.jpg

Lamourish
07-14-07, 07:26 AM
Is that enough light to push a consistent 20ish MPH? I guess that's really the fundamental question here: how much power is necessary?

znomit
07-14-07, 08:24 AM
15W - 20W halogen equivalent should be plenty. For road riding you can certainly get by with a lot less, but its always nice to have a little more.
If you are going to be doing this every day then a decent backup light is a good idea too.

Lamourish
07-14-07, 08:49 AM
15W - 20W halogen equivalent should be plenty. For road riding you can certainly get by with a lot less, but its always nice to have a little more.
If you are going to be doing this every day then a decent backup light is a good idea too.

So around 400ish lumens (from post above) should do the trick?

socalrider
07-15-07, 02:41 PM
The amount of light you need is also depednent on how much street lighting you have.. Most of the streets I ride at night have decent street lighting and find that riding at speed is no problem with a decent light.. I switch between using my fenix lights and my hid...

If I lived in a rural area with dark roads I would want the most light I could afford.. Obviously the Lupine lights are the cream of te crop.. I am still excited about seeing there new light next month.. Regardless of what I am using on the bars I always supplement with my Fenix P2d on my helmet..

Helmet lights in addition to bar mounted lights help tremendously, expecially at seeing through dark corners or getting the attention of drivers.. You look right at them with your helmet light and you get there attention which is a key for safety at night..

Lamourish
07-15-07, 07:42 PM
The Lupines are sexy, no doubt about it. But that's alot of money. I have about 1-2 miles with absolutely no light, so I'm essentially planning to cover the path with a light, if possible. You do bring up a good point about visibility, but I only want to buy one light, and was leaning toward a helmet light.

Along the lupine lines, would I have to go Wilma X or is there a lower model that would work?